Pipe flaring tool



April 24, 1952 R. TEMPLEv a1-AL 3,031,007

PIPE FLARING TooL Filed Aug. 29, 1960 2 sheds-sheet 1 W m d" E* LSUIUHUHHIHWIII IN V EN TORS. POBEPT TEMPLE, BYEP/VEJ T E. TEMPLE,

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April 24, 1962 R. TEMPLE ET AL 3,031,007

PIPE FLARING TOOL Filed Aug. 29, 1960 2 Sheets-Sheet 2 1N V EN TORS XROBERT TEMPLE,

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United Statee 3,031,007 PIPE FLARING T001.

Robert Temple, Swissvale, and Ernest E. Temple, Murrysville, Pa.,assignors to Mine Safety Appiiances Company, a corporation ofPennsylvania Filed Aug. 29, 1961i, Ser. No. 52,4199 6 Jlaims. (Cl.153-81) This invention relates to tools for flaring the ends of pipes,and more particularly to such tools that are actuated by explosivecharges.

In a copending patent application, Serial No. 823,729, tiled June 29,1959, now Patent No. 2,993,522, several pipe Haring tools are shown thatare of the same type as disclosed in this application. After any ofthose tools has been used, the breechblock is removed and then a specialrod is inserted in the rear end of the tool and screwed into a threadedhole in the rear end of the piston so that the piston can be pulled backinto its retracted position ready for use again. Retracting the pistonin that manner requires the presence and use of the separate retractingro-d, which may be mislaid or not be present for some other reason.

It is among the objects of this invention to provide an explosivelyactuated pipe flaring tool, in which the piston can be retracted by apermanent part of the tool, in which the retracting part of the toolholds the piston in its rear position until considerable pressure buildsup behind it, and in which sealing gaskets are not required.

The preferred embodiment of the invention is illustrated in theaccompanying drawings, in which FIG. l is a plan view of our pipe daringtool;

FIG. 2 is a vertical longitudinal section;

FIG. 3 is a View of the front end of the tool showing thepipe-positioning pin in place;

FIGS. 4 and 5 are cross sections taken on the lines IV-IV and V-V,respectively, of FIG. l; and

FIG. 6 is a view similar to FIG. 2, but showing the tool after itscartridge has been fired.

Referring to FIGS. 1 to 5 of the drawings, a hollow housing 1 has aninternally threaded cylindrical rear end, and a front end provided withan open-top pipe-receiving recess 2. Between its ends the housing isopen at the top to permit insertion of a die 3 and a die retainer 4. Thechamber that receives the die retainer has parallel opposite sides 6.The rear portion of the retainer is provided with a recess havingopposed forwardly converging side walls 7 that are engaged by theforwardly converging sides of the die. The die is provided with acentral pipe-receiving opening 8, the rear end of which is flared to theextent necessary to provide the desired are on a pipe 9. To permit thedie to grip the pipe, as will be explained presently, and also to allowthe die to be removed from the flared pipe, the die is made in two partsor segments which are spaced apart laterally along its center. As shownin FIG. 4, the two segments may be held adjacent each other by studs 11slidably mounted iu bores 12.

The housing 1 is provided directly behind the die with a pair ofdiametrically opposite holes 13 for receiving a removable pin 14 thatserves as a stop or locator for the end of the pipe. That is, the pipeis pushed back through the die until it engages the pin, to insure thatthe same length of every pipe will be ared. After the pipe has beenpositioned in this manner, the pin is removed before the tool isoperated.

Screwed into the rear end of housing 1 is the enlarged front end of along tubular holder 16 for sleeve means 17 slidably mounted in the frontportion of the holder. Separation of the holder and housing normally isprevented by a locking stud 1S screwed into the wall of the housing andprojectingV into its rear end behind the en- Sl? Patented pr. 2d, 1962larged front end of the holder. Preferably, the sleeve means takes theform of an integral sleeve. Although the chamfered inner end of thesleeve may normally engage the holder, it is preferred to space themapart slightly and to enlarge the inner diameter of the holder, near itsfront end, and the adjoining portion of the sleeve so that engagingradial shoulders 19 and 20 are formed, by which the sleeve can be movedahead when the holder is screwed farther into the housing. When thathappens, the sleeve will move die 3 forward against the converging wallsof the die retainer 4, which will force the two segments of the dietoward each other to grip the pipe between them. Then the positioningpin 14 can be removed from the housing. The front end of the sleeve isprovided with a pair of notches 22 that receive the pin while it extendsthrough the housing. rI'hey are maintained in alignment with housingholes 13, even when the tubular holder is turned in the housing, by apositioning stud 23 screwed into the wall Vof the housing and extendinginto a longitudinal slot 24 in the front end of the sleeve.

It is a feature of this invention that the internal diameter of the rearportion of tubular holder 16 behind sleeve 17 is reduced and slidablyreceives a barrel 26. The front end of the barrel is enlarged and isprovided with a rearwardly facing tapered shoulder 27 that normallyengages a forwardly flaring seat 28 in the holder. The rear end of thebarrel is threaded and extends out of the holder. Screwed onto thebarrel far enough so that it is always inside the holder, is a collar29. At diametrically opposite points, this collar is provided withthreaded radial openings, in which the inner ends of straight handles 31are screwed. These handles extend out through slots 32 extendinglengthwise of the tubular holder. The handles permit the barrel to beslid forward and back in the holder, but they keep it from rotating sothat a breechblock 33 can be screwed onto its projecting end and upagainst the rear end of the holder to pull barrel shoulder Z7 backagainst its seat 2S. Mounted in the breechblock is a tiring pin 34 thatcan be driven forward by a hammer or the like to detonate a cartridge 36disposed in a cartridge chamber 37 formed by the rear end of the barrel.

Slidably mounted in sleeve 17 is a piston 40. In front 0f the pistonthere is pipe-flaring means spaced from the die. This means may be aseparate element or, as shown, a forwardly tapered head 41 forming thefront end of the piston itself. The taper of head 41 is the same as theflaring rear end of die opening 3. T o provide a good seal between thepiston and sleeve, the piston may be provided with a circumferentialgroove, in which an O- ring 42 is mounted. To normally hold the pistonin its rear or retracted position in the sleeve, it is provided with aforwardly extending tapered axial bore 43 that receives and frictionallyengages a forwardly tapered projection 44 on the front end of thebarrel. There is only a slight taper to the engaging surfaces of theprojection and bore so that they can be wedged tightly together byforcing the projection into the bore when the barrel is pushed forwardin the holder. The front end of the barrel itself is provided with aplurality of passages 45 that connect the inside of it with a spacebehind the piston and the sleeve.

When the tool has been loaded and a pipe has been properly positioned init, with the sleeve pressed up against the die, all as shown in FlGS. 1and 2, the rear end of firing pin 3d is struck in order to detonate thecartridge. The resulting gases expand through passages 45 in the frontend of barrel 26 and drive both the piston 40 and sleeve 17 forward.Since the sleeve already is in engagement with the die but flaring head41 is spaced from the die, the first thing that will occur is that thedie will be driven`forward slightly by the sleeve and thereby caused togrip the pipe so securely that it will not be driven forward through thedie when struck an instant later by the flaring head. Consequently, therear end ofthe pipe will be expanded or flared into the rear end of thedie opening as shown in FIG. 6.

The tight tit between the piston and the barrel projection requiresconsiderable gas pressure to be built up behind the piston before itwill move forward. This insures high velocity of the piston when itleaves the barrel projection. The same gas pressure forces the barrelbackward tightly against its seat 28 and thereby forms a good sealwithout the use of a sealing gasket.

Before the ared pipe is removed from the tool, the breechblock isremoved and then the handles 31 on the barrel are gripped and the barrelis pushed forward to wedge its projection 44 into the tapered bore 43 inthe piston. The barrel then is pulled back to its rear position, withthe piston moving with it. The tubular holder 16 then is retractedsomewhat in housing 1 to permit the pipe and die and die retainer to beremoved through the top of the housing. After a new pipe has beeninserted in the die and pressed up against positioning pin i4, which hasbeen inserted in the meantime, the tubular holder is screwed tightlyinto the housing to cause the die to grip the pipe. Then pin 14 isremoved, a new cartridge is inserted in chamber 37, and the breechblockis screwed onto the rear end of the barrel. The tool is now ready totire and flare the end of the pipe.

By connecting pin 14 to the breeckblock by means of a lanyard 47 that isshort enough, it can be made impossible to screw the breechblock ontothe rear end of the barrel until after the positioning pin has beenpulled out of the housing. Consequently, there is no danger ofinadvertently tiring the tool while the pin is still in place. Thelanyard may be permanently fastened to the tool by running it through ahole 4% through the head of locking stud 18. This also prevents the studfrom accidentally coming out of the housing.

According to the provisions of the patent statutes, we have explainedthe principle of our invention and have illustrated and described whatwe now consider to represent its best embodiment. However, we desire tohave it understood that, within the scope of the appended claims, theinvention may be practiced otherwise than as specifically illustratedand described.

We claim:

l. A pipe tiaring tool comprising a die provided with a centralpipe-receiving opening aring at its rear end, the die having outersurfaces converging toward its opposite end, sleeve means having a frontend engageable being separated into spaced segments slidable forwardagainst said retaining member surfaces, a tubular holder slidablyreceiving the sleeve means, means connecting said holder with theretaining member for longitudinal adjustment of the holder toward andaway from the retaining member, a barrel slidably mounted in said holderbehind the sleeve means and having a cartridge chamber at its rear end,removable means at the rear end of the barrel normally holding it in arear position, said holder when adjusted toward the retaining memberbeing formed to push said sleeve means forward against said die to causethe die to grip the end of a pipe in the die opening, pipe aring meansbehind the die and normally spaced therefrom, a piston in said sleevemeans behind said Haring means, the barrel having an opening connectingsaid cartridge chamber with the rear ends of the sleeve means andpiston, means for firing a cartridge in said chamber to drive the sleevemeans and piston forward to move said liaring means into pipe flaringposition in the tiared end of the die opening, the front end of thebarrel and the rear end of said piston having frictionally engageablesurfaces, and means connected with the barrel for manually moving itforward in the tubular holder after removal 0f said removable means,whereby to force said friction surfaces into engagement with each otherto permit the piston to be pulled back in the sleeve means.

2. A pipe flaring tool as recited in claim 1, in which the barrel isprovided with a rearwardly facing shoulder and said holder has a seatnormally engaged by said shoulder.

3. A pipe flaring tool as recited in claim 1, in which said frictionallyengageable surfaces are formed by a forwardly tapered projection on thefront end of the barrel and a forwardly tapered bore in the rear end ofsaid piston receiving said projection.

4. A pipe iiaring tool as recited in claim l, in which the barrel isprovided with a rearwardly facing shoulder and said holder has a seatnormally engaged by said shoulder, and said removable means is screwedonto the rear end of the barrel and against the rear end of the tubularholder and holds said shoulder against said seat.

5. A pipe aring tool as recited in claim 1, in which the side of thetubular holder is provided with a longitudinal slot, and said means formoving the barrel forward extends through said slot.

6. A pipe liaring tool as recited in claim 5, in which said removablemeans is screwed onto the rear end of the barrel and against the rearend of the tubular holder.

References Cited in the file of this patent UNITED STATES PATENTS2,276,259 Temple Mar. 10, 1942 V2,464,510 Hull Mar. 15, 1949 2,861,623Frank Nov. 25, 1958 FOREIGN PATENTS 543,506 Great Britain Feb. 27, 1942

